Method of making an innerspring foam mattress



July 30, 1963 J. J. wETzLER 3,099,518

METHOD OF MAKING AN INNERSPRING FOAM MATTRESS original Filed May 28.1957 4 sheets-snaai 1 ATTORNEYS July 30, 1963 J. J. wETzLER 3,099,518

METHOD OF MAKING AN INNERSPRING FOAM MATTRESS Original Filed May 28.1957 4 Sheets-Sheet 2 FIG. 5

4 Sheets-Sheet 5 July 30, 1963 J. J. wE'rzLER METHOD OF' MAKING ANINNERSPRING FOAM MATTRESS Original Filed May 28. 1957 July 30, 1963 J.J. wETzLx-:R 3,099,518

METHOD oF MAKING AN TNNERSPRTMG FOAM MATTRESS 4 Sheets-Sheet 4 OriginalFiled May 28. 195'? INVENTOR Just/'n J Weiz/er ATTORNEYS United StatesPatent O 3,099,518 METHOD F MAKING AN INNERSPRING FOAM MATTRESS JustinJ. Wetzler, Evanston, Ill., assiguor to The Englander Company, Inc.,Chicago, Ill., a corporation of Delaware Original application May 28,1957, Ser. No. 662,085. Di-

vided and this application May 16, 1960, Ser. No.

This invention relates to methods of making resilient mattresses, moreparticularly to methods of making resilient mattresses embodying aplurality of springs embedded in a resiilent rubber-like foam structure.

This application is a division of prior application Serial No. 662,085led May 28, 1957, for Foam Mattresses.

The resilient rubber-like foam structure referred to hereinabove issuitably one of the conventional urethane foams prepared by the reactionof a polyisocyanate (usually, a diisocyanate) with an organic substancehaving a plurality of groups or radicals each containing reactivehydrogen, for instance, a polyester 0r a polyether or one of thesubstances disclosed in the patent to Hanford et al. No. 2,284,896. Notethe article entitled Polyethers for Urethane iFoams on page 78 ofJanuary 2l, 1957, issue of Chemical and Engineering News. Methods ofmaking specific foams are disclosed, for instance, in the patents toSimon et al. Nos. 2,577,279, 2,577,280, 2,591,884, 2,602,783, 2,698,838,and 2,764,566; in the patent to Hill No. 2,726,219; and in the patent toReis No. 2,779,689. The chemical processes and reactions involved in theformation of urethane foams are well known to those skilled in the artand per se form no part of the present invention. Hence, no furtherreference will be made t0 the chemistry of urethane foams except tonote, at this time, that urethane foams may be formed by mixing,appropriate reactants and depositing the resultant mixture on a surfaceas a thin layer. Then a chemical reaction occurs accompanied by theevolution of gas. Thus, a layer originally one-half inch thick may foamup to a thickness of perhaps four inches. This foaming action may becompleted within 3 or 4 minutes. Transformation of the originally liquidreactant mixture into a more or less resilient, rubber-like cellularsolid takes place concurrently vvith the gas forming foaming reaction.

In making a mattress, pad or cushion according to the present invention,Ia spring structure is first provided. The individual springs of thisspring structure are then each covered with a water resistant filmyplastic coating which externally bridges the convolutions of theindividual springs, so that each individual spring is enclosed within aseparate film envelope. Such coating compositions and spraying ordipping methods for applying the same are conventional andare well knownto those skilled in the art. lExamples are given, for instance, in thepatents to Phillips et al. No. 2,394,101 and to Pineles No. 2,441,227.'Ille compositions in question form per se no part of the presentinvention.

When the above noted spring structure has been provided with aprotective lm envelope around each individual spring, the springstructure is embedded within a urethane foam slap or layer. Theresulting unitary structure may be used as such a mattress, pad orcushion. Or, if desired, other and further layers of padding may beprovided therearound, and the structure may be enclosed Within anydesired cover or casing.

Other and further features of the present invention will become apparentfrom the following description and appended claims as illustrated by theaccompanying drawings which show diagrammatically and by way of examplesmattresses made according to the methods of the present invention.

Claims.

ICC

FIG. 1 is a vertical longitudinal cross sectional view taken along theline 1-1 of FIG. 2 and showing apparatus for making a mattress accordingto the present invention;

FIG. 2 is a cross sectional View taken along the line 2-2 of FIG. 1;

FIG. 3 is an enlarged fragmentary cross sectional view taken along theline 3--3 of FIG. 1;

FIG. 4 is a fragmentary View similar to FIG. l and nhowing amodification of one detail in the apparatus of i IG. 1;

FIG. 5 is a perspective view of a coil spring enclosed within a plasticfilm envelope preparatory to incorporation with a mattress unitaccording to the method illustrated in FIGS. 1-3.

FIG. 6 is a cross sectional 'View taken along the line 6-6 of IFIG. 5;

FIG. 7 is Ian enlarged fragmentary vertical cross sectional view througha mattress made according to the method of FIGS. 1-3 and including coilssuch as that illustrated in FIGS. 5 and 6;

FIIG. 8 is a fragmentary plan view showing a plurality of coil springsinterconnected to form a unit suitable for interconnecting within amattress;

FIG. 9 is a fragmentary cross sectional view taken along the line 9 -9of fFIG. 8 and shows a mattress incorporating the interconnected springsof FIG. 8;

FIG. 10 is a view similar to FIG. 8 but shows a spring unit of slightlydifferent construction;

FIG. 11 is a fragmentary cross sectional View taken along the line11--11 of FIG. 10 and shows a mattress incorporating the spring unit ofFIG. 10;

FIG. 12 is a perspective view of a coil spring held in slightlycompressed condition and enclosed within a plastic envelope preparatoryto incorporation with a mattress;

FIG. 13 is a fragmentary plan View showing another plurality of coilsprings interconnected to form a unit suitable for incoporation swithina mattress;

FIG. 14 is a cross sectional View taken along the line 14-14 of FIG. 13and shows a mattress incorporating the interconnected springs of FIG.13;

FIG. 15 is a fragmentary plan view showing another set of coil springsinterconnected for incorporation in a mattress;

FIG..16 is a cross sectional View taken along the line 116-16 of FIG. 15and shows a mattress incorporating the springs of FIG. 15;

FIG. 17 is a fragmentary plan view of a plurality of coil springs tiedtogether preparatory to incorporation within a mattress;

FIG. 18 is a cross sectional view taken along the line 18-18 of FIG. 17and shows a mattress incorporating the springs of FIG. 17;

' FIG. 19 is a fragment-ary plan view showing a plurality of coilsprings interconnected preparatory to incorporation within a mattress;

FIG. 20 is a cross sectional view taken along the line 20%20 of FIG. 19and shows a mattress including the springs of FIG. 19;

FIG. 21 is a longitudinal vertical cross sectional view similar to FIGS.14, 16, 18 and 20 and showing a mattress similar to that made accordingto the methods of FIGS. 1--3 and including an outer layer of padding anda mattress cover or ticking; and

' FIG. 22 is a perspective View showing how the coil springs areenclosed within a plastic film envelope.

[Reference is now made to FIGS. 1-3 which show apparatus employed in themethods of the present invention including a lower belt `10 travellingover horizontal spaced rollers 12 and 14 and supported therebetween by alower shoe 16. Suitable conventional means are provided for causing thebelt 10 to travel from the left to the right.

An upper belt 18 moving over rollers 2i) and 22 likewise is caused tomove from the left to right by any suitable conventional means. Theupper roller 22 is aligned vertically with the lower roller 14. Theupper roller 2b is oiset to the right with respect to the lower roller12. A shoe 24 holds the horizontal portion of the belt 18 against upwarddisplacement. A pair of vertical sidewalls members 26 and '28 serve tocomplete enclosure of the space between the lower belt 18 and the upperbelt 18. A hopper 30 serves to discharge material received from aconduit 32 onto the lower belt 18 to the left of the roller 20.

In the operation of the apparatus of FIGS. 1-3, a strip of urethane foamrubber 34 is caused to travel along with the belt 19 over and above thehorizontal reach of the latter belt and another strip 36 of urethanei-oam rubber is caused to travel along and below the horizontal reach ofthe bel-t 118. Sets of interconnected coil springs generally indicatedat 48 are introduced between the urethane -foam rubber strips 34 and 36for travel therewith between the sidewalls or guides 26 and 28.

As shown in FIG. yl each spring assembly 48 is initially disposed onythe urethane ifoam ystrip 34. While the Vspring assembly 4? is in thisposition, =a urethane foam forming mixture 42 is deposited on the strip34 `from the hopper 30. Originally, this more or less viscous but stillliquid .foam forming mixture 42 does not extend to the top of the springassembly 40. However, as `the latter travels `from left to right, the`formation of team in the mixture 42 causes the latter to rise to thetop of the spring assembly 48 and into contact with the underside Iofthe upper urethane foam strip 36. `It will be noted that the lowerrollers 12 and 114 and the upper rollers 26 and 22 are spaced apart sothat the spring assembly 40' will t exactly between the two urethane-foam rubber strips 34 and 36, the latter being held in position by thetwo shoes 16 and 24.

The -spring assembly `40 includes upper and lower wire trames y44 and 46extending therearound; a plurality of individual coil Isprings i48; andupper and lower `sets of crossing or intersecting the wires 58interconnecting the coil springs 48 with each other and with the iframes44 and 46. Further, as shown in `FIGS. and 6, each individual coilspr-ing 48 is enveloped by a iilm 52.

'I'he resulting mattress structure is illustrated in FIG. 7 as includingcoil springs 48 each individually enveloped by a ilm 52 and allinterconnected to each other and to the frames `44 and 46 by means ofcrossing Wires 50` to form a spring assembly "401 embedded within anintegral urethane foam structure made up of the lower strip 34, theupper strip 36 and the material 42 deposited from the hopper 3()E and,when completely polymerized, bonded to and connecting the .two strips 34and 36 to form therewith an integral ttoarnstructure.

lt should be understood that the rubber strips 34 and 36 may becontinuous so that as successive spring assemblies 40 are -fedtherebetween and foam forming liquid 42 is deposited on the lower strip34, there is formed `a continuous foam structure embedding successivespring assemblies 49 trom which individual mattresses may be isolated bysevering this structure between the spaced ends of the spring assemblies40. However, if desired, it is also possible to make the foam strips 34and 36 discontinu-ous, individual strip units being tfed in pairsbetween the belts lil and 18 in proper synchronization with spr-ingassemblies 40 .to lform `a continuous strip held together only by Vfoamforming material `42 extending between the sp-aced ends of successivespring assemblies 48. Then, to isolate individual mattresses, it is onlynecessary Vto sever the connecting foam material 42 between the spaced`ends of the spring assemblies 48.

Ordinarily, the spring assembly 48 is completely assembled `from itsconstituent .parts (coils 48, wires Si) and nframes 44 `and 46) andthereafter the coil springs 48 are dipped or sprayed with a tlmtorni-ing material to i enclose each spring 48 within a iilmy envelope52. Such iilmy envelope may be formed by the technique described in US.Patent 2,441,227. Such technique comprises directing, at a small angletangential to the spring convolutions, a spray of comparatively long,comparatively dry adhesive filament across the space between the springconvolutions to progressively build up a bridging coating of a networkof randomly oriented iilarnents and then spraying the bridging withwetter and smaller adhesive spray particles to -form a continuousexterior sheath or unitary plastic envelope 52 around the spring coils48.

The foam forming material 4t2 can be deposited on the spring assembly`46 and the lower lfoam strip 34 by any suitable conventional means. Asshown in IPIG. 4, such deposition of foam forming material may also beeliected by means of a pair of spray nozzles 6i) and 62 each serving todeposit, in one and the same area, for mutual admixture, two componentswhich when mixed constitute a -foaming urethme forming composition.

Any desi-red conventional type of spring assembly adapted -for use in amattress, pad or cushion may be embedded within a urethane foamstructure utilizing the apparatus and :method -disclosed hereinabove.Reference is made to FIGS. `8 2() yas showing mattresses, pads orcushions including various types of conventional spring assembliesembedded within an integral urethane foam structure, each individualcoil spring in said assemblies being encl-osed within an individual ilmyenvelope.

As sho-wn in FIGS. -8 and 9, a plurality of coil springs 64, eachenclosed within la lfilmy envelope 66, are held in assembledrelationship within upper and lower wire frames 68 and 70 by means oflongitudinally extending wires 72, The springs :64 are arranged inspaced rows, the springs in each row being close together. rIihe wires70 extend transversely of these rows of springs. Short wires 76 tie thesprings 64 to the wires 72.

FIGS. 10 and -11 illustrate hour glass shaped coil springs 80 eachenveloped by an individual film 82 and held within upper and llower wiretrames 84 and 86 by means of wire coils 88 engaging pairs of closelyspaced coils 80 which are arranged similarly to the coils 64 of FIG. 8.

FIG. 12 shows a coil spring 90 of barrel shape held in slightlycompressed state by means of a tape 92 crisscrossing through the centerof the coil 'and extending vertically along opposite sides of the coil.structure is enclosed within a lmy envelope 94 and may be assembled intospring assemblies similarly `to the coil 48 of FIGS. 5 and 6.

FIGS. 13 and 14 show hour glass shaped springs 100 each enclosed withina lmy envelope i102 and held within upper and lower trames 104 and 106by means of 4crossing, pieces of wire coil 108 extending betweendiagonally opposed adjacent .coils .100.

FIGS. 15 and 16 show hour glass shaped coil springs 11@ each enclosedwithin a iilmy envelope 112 and held in assembled relationship withinupper and lower frames i114 and 116 by means loi? intersecting upper andlower tapes 118. rPhe springs .1110 are held in slightly compressed-state by looped wires ,119 extending within the center of each springbetween Ithe upper and lower tapes 118.

FIGS. 17 and 18 show hour glass shaped coils 120 each enclosed within anlmy envelope i122 and all held in closely spaced assembled relationshipwithin upper and lower frames .124 and i126 by short pieces of wire 128`tying the coils y1Z0` together.

FIGS. 19 and 20 show hour glass shaped coils 130 each enclosed within aiilmy envelope 132 and all held in :spaced assembled relationship withina trame 1-34 extending at about a middle level by steel tapes 136.

FIG. 21 shows 4a mattress including an integral urethane foam structure146 and coil springs 142 each en-` closed within a lmy envelope 144embedded within the foam ystructure 140 and held in assembledrelationship within upper and lower frames 146 and 148 !by intersectingwires 150. The mattress further includes padding 152 and an outer coveror ticking 154.

Many details may be varied without departing from the principles of thisinvention and it is therefore Inot my intention to limit the patentgranted on this invention otherwise than necessitated lby the scope ofthe appended claims.

The invention is claimed as follows:

l. A method of making a resilient mattress which comprises providing aplurality of coil springs i-n a predetermined pattern with spacestherebetween, enclosing each of said coil springs with individual lilmyplastic envelopes, and thereafter embedding the coil springs within lapad of resilient cellular material, said last mentioned step includingforming portions of the resilient cellular material in -said spacesbetween the springs so that said portions of the resilient cellularmaterial intimately confonm to the lilmy envelopes enclosing thesprings.

2. A method of making a resilient mattress which comprises providingunidirectionally moving lirst and second spaced parallel :strips ofresilient cellular material, providing a plurality of coil springs,enclosing each coil spring within a lmy envelope, thereafter disposingsaid coil springs on said rst strip, superposing said second strip onsaid coil springs, and `during movement of the strips filling the emptyspace -between said strips and the films around sai-d springs withmaterial yielding resilient cellular material bonded to said strips.

3. A method according to claim 2 in which said cellular material isflexible urethane foam.

4. A method according to claim 2 comprising the further step ofinterconnecting said coil springs before disposing said springs on saidrst strip but after each spring has -been enclosed within a ilmyflexible envelope.

5. A method of making `an innerspring foam mattress which comprise-sencasing each of a series of springs within a unitary ilexible plasticsheath, interconnecting the plastic-encased springs with each other andwith a frame to form a spring assembly; providing upper and lowercontinuously and unidirectionally moving spaced parallel strips ofresilient cellular material, continuously disposing successive 4'springassemblies on the said lower strip of cellular material, continuouslyflowing `.a liquid foamable composition onto said lower strip, foamingsaid composition in situ between said moving upper and lower strips andbetween said plastic-encased spr-ings and continuously severing theresulting structure between spaced ends of said successive springassemblies.

References Cited in the file of this patent UNITED STATES PATENTS Re.24,9514 Koenigsberg Dec. 20, 1960 2,161,080 Murphy et al June 6, 19392,247,543 Bernstein July 1, 1941 2,398,237 Marsack Apr. 6, 19462,415,765 Schmidt Peb. 1l, 1947 2,434,209* Glazier Jan. 6, 19482,446,775 Marsack Aug. 10, 1948 2,576,073 Kropa etal. Nov. 20, 19512,744,042 Piace May 1, 1956 2,753,642 Sullivan July 10, 1956 2,882,959Burkart Apr. 2l, 1959 2,927,876 Hoppe et al Mar. 8, 1960 2,983,636Runton Mray 9, 1961 2,994,890 Wagner Aug. 8, 1961 FOREIGN PATENTS577,705 Great Britain Mar. 29, 1946 842,267 Germany Sept. 15, 1952

1. A METHOD OF MAKING A RESILIENT MATTRESS WHICH COMPRISES PROVIDING APLURALITY OF COIL SPRINGS IN A PREDETERMINED PATTERN WITH SPACESTHEREBETWEEN, ENCLOSING EACH OF SAID COIL SPRINGS WITH INDIVIDUAL FILMYPLASTIC EMVELOPES, AND THEREAFTER EMBEDDING THE COIL SPRINGS WITHIN APAD OF RESILIENT CELLULAR MATERIAL, SAID LAST MENTIONED STEP INCLUDINGFORMING PORTIONS OF THE RESILIENT CELLULAR MATERIAL IN SAID SPACESBETWEEN THE PRINGS SO THAT SAID PORTONS OF THE RESILIENT CELLULARMATERIAL INTIMATELY CONFORM TO THE FILMY ENVELOPES ENCLOSING THE SPRINGS